<!DOCTYPE html>
<html lang="en">
     <head>
         <meta charset="utf-8">
         <style type="text/css">
             .fullscreen
             {
              position:absolute;
              left: 0;
              top: 0;
              width: 100%;
              height: 100%;
             }
         </style>
     </head>
     <body>
         <button class="fullscreen" id="buttonOne">Click Me</button>
         <input type="color" id="colorpicker" value="#ff0000" style="visibility:hidden"/>
         <input type="file" id="filepicker" accept=".cpp, .html, .h, .png, .qdoc, .qml" style="visibility:hidden"/>
     </body>
</html>
